The prevalence of diabetes and its associated complications have been assessed in several pacific populations, including Polynesians and Melanesians, living traditional ways of life and in highly urbanized and westernized circumstances. Substantially lower frequencies of diabetes were found in the traditional circumstances and attempts to determine factors responsible for these differences, such as genetic background, physical activity and obesity, have been made. The fortuitous occurrence of epidemic polyarthritis, caused by Ross River virus infection, led to a detailed description of the disease, including redefinition of the incubation period and the discovery of new vectors for the disease. A follow-up study was conducted to determine if infection during pregnancy resulted in fetal or congenital complications.